Merge pull request #9 from saloonphp/feature/add-start-page-property

Feature | Provide custom start page

src/Paginator.php

@@ -30,6 +30,11 @@ abstract class Paginator implements Iterator, Countable
      */
     protected Request $request;
 
+    /**
+     * The start page when the paginator is rewound
+     */
+    protected int $startPage = 1;
+
     /**
      * Internal Marker For The Current Page
      */
@@ -199,7 +204,7 @@ public function valid(): bool
      */
     public function rewind(): void
     {
-        $this->page = 1;
+        $this->page = $this->startPage;
         $this->currentResponse = null;
         $this->totalResults = 0;
         $this->totalPages = null;
@@ -310,6 +315,18 @@ public function getPage(): int
         return $this->page;
     }
 
+    /**
+     * Set the start page of the paginator
+     *
+     * Used when the paginator is rewound
+     */
+    public function setStartPage(int $startPage): static
+    {
+        $this->startPage = $startPage;
+
+        return $this;
+    }
+
     /**
      * Count the iterator
      */

tests/Feature/StartPageTest.php

@@ -0,0 +1,51 @@
+<?php
+
+declare(strict_types=1);
+
+use Saloon\PaginationPlugin\Tests\Fixtures\Connectors\PagedConnector;
+use Saloon\PaginationPlugin\Tests\Fixtures\Requests\SuperheroPagedRequest;
+use Saloon\PaginationPlugin\Tests\Fixtures\Connectors\CustomStartPagePagedConnector;
+
+test('you can specify a start page on a paginator class', function () {
+    $connector = new CustomStartPagePagedConnector;
+    $request = new SuperheroPagedRequest();
+    $paginator = $connector->paginate($request);
+
+    $superheroes = [];
+    $iteratorCounter = 0;
+
+    foreach ($paginator as $item) {
+        $iteratorCounter++;
+        $superheroes = array_merge($superheroes, $item->json('data'));
+    }
+
+    expect($iteratorCounter)->toBe(2);
+    expect($paginator->getTotalResults())->toEqual(10);
+
+    $mapped = array_map(static fn (array $superhero) => $superhero['id'], $superheroes);
+
+    expect($mapped)->toEqual([11, 12, 13, 14, 15, 16, 17, 18, 19, 20,]);
+});
+
+test('you can specify a start page on a paginator instance', function () {
+    $connector = new PagedConnector;
+    $request = new SuperheroPagedRequest();
+    $paginator = $connector->paginate($request);
+
+    $superheroes = [];
+    $iteratorCounter = 0;
+
+    $paginator->setStartPage(3);
+
+    foreach ($paginator as $item) {
+        $iteratorCounter++;
+        $superheroes = array_merge($superheroes, $item->json('data'));
+    }
+
+    expect($iteratorCounter)->toBe(2);
+    expect($paginator->getTotalResults())->toEqual(10);
+
+    $mapped = array_map(static fn (array $superhero) => $superhero['id'], $superheroes);
+
+    expect($mapped)->toEqual([11, 12, 13, 14, 15, 16, 17, 18, 19, 20,]);
+});

tests/Fixtures/Connectors/CustomStartPagePagedConnector.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Saloon\PaginationPlugin\Tests\Fixtures\Connectors;
+
+use Saloon\Http\Request;
+use Saloon\Http\Response;
+use Saloon\PaginationPlugin\PagedPaginator;
+use Saloon\PaginationPlugin\Contracts\HasPagination;
+use Saloon\PaginationPlugin\Contracts\HasRequestPagination;
+
+class CustomStartPagePagedConnector extends TestConnector implements HasPagination
+{
+    /**
+     * Paginate over each page
+     */
+    public function paginate(Request $request): PagedPaginator
+    {
+        if ($request instanceof HasRequestPagination) {
+            return $request->paginate($this);
+        }
+
+        return new class(connector: $this, request: $request) extends PagedPaginator {
+            /**
+             * Set a custom start page
+             */
+            protected int $startPage = 3;
+
+            /**
+             * Check if we are on the last page
+             */
+            protected function isLastPage(Response $response): bool
+            {
+                return empty($response->json('next_page_url'));
+            }
+
+            /**
+             * Get the results from the page
+             */
+            protected function getPageItems(Response $response, Request $request): array
+            {
+                return $response->json('data') ?? [];
+            }
+        };
+    }
+}